MacGregor’s subsea cranes get new fibre-rope retrofit option

MacGregor, a part of Cargotec, has launched a new fibre-rope retrofit option for its subsea cranes.

MacGregor said on Thursday that the modular upgrade replaces the crane’s original steel wire rope with high-performance synthetic fibre rope, using the same technology as MacGregor’s fibre-rope crane, the FibreTrac 1500, which was introduced earlier this year.

The company said that these cranes combine MacGregor’s offshore crane technology with Parkburn Precision Handling Systems’ fibre-rope tensioning technology.

Alexander Nürnberg, Senior Vice President, Technology and R&D, MacGregor, said: “This unique system offers a good investment to our customers to expand their operational window.”

MacGregor noted that the main advantage of the fibre ropes is that it weighs virtually nothing in the water, so regardless of the length of rope paid out it does not add anything to the load experienced by the crane.

This is in complete contrast to steel wire ropes, where the increasing weight of the wire limits the load permissible in relation to depth, the company explained.

According to the company, a 100-tonne fibre-rope crane has the same lifting capacity as a 150-tonne crane with steel wire rope, lifting at a depth of 2,000m; a 200-tonne crane with steel wire rope, lifting at a depth of 3,000m and a 250-tonne crane with steel wire rope, lifting at a depth of 3,500m.

Gaute Sjusdal, Director of Advanced Offshore Solutions, Global Lifecycle Support at MacGregor, said: “By employing this fibre-rope technology, a crane is able to use its full lifting capacity at maximum depths, so a smaller crane and vessel can be used for more assignments. The fibre-rope crane can lift loads at practically any depth that is required, allowing these vessels to bid on a wider range of contracts.”

Furthermore, MacGregor claims the fibre rope can be inspected for wear, internally and externally and can splice in new sections adding great flexibility to the system.

Sjusdal said: “While the entire rope can be replaced if necessary, damaged sections can easily be replaced, and the length can be increased as required.”

He also added that the transportation of the rope requires no special equipment while steel wire ropes require special transportation, handling and spooling and also unlike wire rope, fibre rope does not require lubrication, eliminating a source of pollution.